libmount: (umount) use mount table filter on -c only

The path canonicalization is the worst use-case, it's better to read
all mount table than try canonicalize.

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libmount/src/context_umount.c b/libmount/src/context_umount.c
index 4a4c5bfe5e788169ffcaa5e94d4925db8b363526..e0b7bda112bad410c1f6fa71c246cdcc27294cf9 100644 (file)
--- a/libmount/src/context_umount.c
+++ b/libmount/src/context_umount.c
@@ -78,11 +78,14 @@ int mnt_context_find_umount_fs(struct libmnt_context *cxt,
         * canonicalized. If --no-canonicalize is enabled than the target path
         * is expected already canonical.
         *
+        * Anyway it's better to read huge mount table than canonicalize target
+        * paths. It means we use the filter only if --no-canonicalize enabled.
+        *
         * It also means that we have to read mount table from kernel
         * (non-writable mtab).
         */
-       if (!mnt_context_mtab_writable(cxt) && *tgt == '/' &&
-           !mnt_context_is_force(cxt) && !mnt_context_is_lazy(cxt))
+       if (mnt_context_is_nocanonicalize(cxt) &&
+           !mnt_context_mtab_writable(cxt) && *tgt == '/')
                rc = mnt_context_get_mtab_for_target(cxt, &mtab, tgt);
        else
                rc = mnt_context_get_mtab(cxt, &mtab);
@@ -257,12 +260,16 @@ static int lookup_umount_fs(struct libmnt_context *cxt)
 
                const char *type = mnt_fs_get_fstype(cxt->fs);
 
+               DBG(CXT, ul_debugobj(cxt, "umount: disable mtab"));
+
                /* !mnt_context_mtab_writable(cxt) && has_utab_entry() verified that there
                 * is no stuff in utab, so disable all mtab/utab related actions */
                mnt_context_disable_mtab(cxt, TRUE);
 
                if (!type) {
                        struct statfs vfs;
+
+                       DBG(CXT, ul_debugobj(cxt, "umount: trying statfs()"));
                        if (statfs(tgt, &vfs) == 0)
                                type = mnt_statfs_get_fstype(&vfs);
                        if (type) {